Fuel dripping from breather tube

Joined Aug 2014
121 Posts | 86+
Oviedo/Orlando, FL
Would like to hear opinions...

1299S with 700 miles...
Added Termi Evo Slip-Ones, Changed Oil, Changed Air Filter (MWR) and Removed Charcoal Canister

When I removed the charcoal canister, I tee-d the coolant over flow to the breath hose line.

A few days ago, I noticed some "fluid" coming from belly pan. It smells like gas, but a little sweeter, and does not fully evaporate. Golden in color. Also the tank was venting like crazy when hot... hissing loudly. I would open the cap, release pressure, and within seconds it was doing it again.

Using compressed air, I verified that breather tube is not obstructed (after disconnecting it from the T). If my knowledge is correct, an obstruction in hose can create these issues (tank under pressure and some type of leak when hot).

I decided to separate the lines (for now) in case the tee connection was creating an obstruction.

Questions:

Would an obstruction in the line create excessive pressure in the tank? (notice that since the original post, two very high end technicians have inspected the lines and blew compressed air through them).

Could this obstruction also cause the dripping fuel? (The answer to this is yes, but it no longer seems to be the case).

Is there anything I could have done when taking the tank off to change the filter that could cause have caused this? (I am assuming the answer to that the breather line could have been pinched, but have verified by puling the ECU panel and lifting the tank, as well as blowing air through the line, that this is not the case).
 
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A small video update to the problem as it continues to perplex me...

[youtube]nQnJiIaGA8E[/youtube]

Noticed a heavy fuel smell a few days ago with some fuel coming out of the breather hose. The top end of the motor seems to be getting hotter than normal, but this could be in my head.

Checked both the breather and overflow lines visually by removing the ecu side panel and lifting the tank. Finally, I removed the lid assembly from the gas tank to access the breather and overfill vac lines and blew low-pressure compressed air through them to see if they were occluded. Both flowed air perfectly at low pressure with zero issues and vented correctly.

However, when the bike is run at operating temperature (210-220 F) for 20 minutes, and then allowed to set, it will begin to drip fuel and the pressure in the tank will spike. The fuel will begin to boil inside the tank.